1. Field of the Invention
The present invention relates to industrial processes involving the use of activated carbon. More particularly, the present invention relates to methods and apparatus for scrubbing activated carbon.
2. The Prior Art
Activated carbon is widely used in the chemical process industry to absorb hazardous materials. In addition, power plants are also turning to adsorption to process exhaust containing hazardous materials. Activated carbon and other adsorbents are being used to capture mercury in these industries. New regulations in the United States are forcing power plants to reduce mercury by 90%. The injection of activated carbon is the route many operators will take. This application of activated carbon requires an increasingly large volume of this material. According to some estimates, the market for activated carbon in the United States will effectively double. According to one source, annual industrial adsorption revenue in NAFTA is about $235 MM per year. In east Asia, the fastest growing region, it is about $430 MM/yr.
One of the problems with activated carbon is that it ends up being converted to fly ash, much of which is sold to be used as a component in cement. The carbon, however, decreases cement strength. One solution for this has been the development of “cement friendly” activated carbon materials. If the activated carbon has been used to absorb mercury, a solution has to be found for removing the mercury before the carbon is incorporated into cement.